Tag Archives: Richard Muller

Richard Muller Radio Rambles, part 1: Kochs “very deep”, “very thoughtful” and “properly skeptical”

A recent Canadian radio appearance by Berkeley Earth founder Richard Muller has shed additional light on the role of Charles Koch, a major funder of the Berkeley Earth effort (and arguably the top funder of climate contrarians over the last several years). In the interview on CBC’s Sunday Edition, Muller mounted his most spirited and detailed defence of Koch yet, describing the oil billionaire as “very thoughtful” and “properly skeptical” of climate science. And the Berkeley Earth website goes even further, linking to an official Koch statement that makes the preposterous claim that the Charles Koch Foundation supports “sound, nonpartisan, scientific research”. That rings especially hollow this election season, given the current massive pro-Republican and anti-regulation push by fossil fuel interests, led as usual by Koch Industries. Continue reading

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Berkeley Earth, part 1: Divergences and discrepancies

[UPDATE 08/17: In comments, Berkeley Earth team member Zeke Hausfather reveals that most of the discrepancy between the Berkeley Earth 2011 and 2012 results is due to a previously unreported error in latitudinal weighting in the earlier version.

UPDATE 08/20: The 2012 GHCN-only series has been uploaded by Zeke Hausfather. Also, I have added clarifications concerning absolute temperature uncertainty and data availability. The summary has been updated accordingly.]

The recent Berkeley Earth land-surface average temperature series is based on a greatly expanded database of station temperature data, along with a completely automated statistical averaging process. In contrast, established average temperature series from NOAA, NASA and HadCrut are based primarily on the smaller Global Historical Climate Network (GHCN) database, and use empirically derived homogenization methods to remove known biases, albeit supplemented by pure statistical methods.

Here, the post-1950 Berkeley Earth “complete” land series is compared to the preliminary Berkeley series released in 2011, as well as to GHCN-only simulated series, based on overall attributes of those unreleased series provided in the Berkeley Earth companion “methods” paper. The 2011 and 2012 “full” (ALL) series Berkeley versions both fall squarely in the range of the latest comparable series from the three other groups post-1950. However, the two Berkeley ALL series diverge over the 1980-2010 period, and lie completely outside each others’ 95% confidence intervals in the 2000s, when baselined to 1950-1979. This turns out to be due to a significant error in latitudinal weighting in the 2011 ALL series; the error was not publicly disclosed at the time of correction. The GHCN 2012 series falls halfway between the 2012 ALL and 2011 ALL series in the 2000s; 2012 GHCN and 2012 ALL each appear to diverge outside the other’s confidence interval in the 2000s. As well, there is an increasing widening between the 2012 GHCN and ALL  series the further one goes back before the 1950-1979 baseline period, with the ALL series about 0.3 C cooler in the early 1800s.

Other issues requiring further analysis are also identified, particularly a reported reversal in the long-term trend of narrowing diurnal temperature range starting in 1987, which contradicts previous GHCN-based analyses.Taken together, these issues cast doubt on the robustness of the present Berkeley Earth analysis, and point up the need for more open data access and improved diagnostics in order to further assess the reliability of the Berkeley Earth approach to surface temperature analysis.

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